PLATE 15. 



Bones of the fossil Finback Whale referred to \Balaenoptera sursiplana, from the Miocene deposits of Gay 

 Head, Martha's Vineyard, Mass. 



Figs. 1, 2, 3. Anterior views of three caudal vertebrae from near the end of the series, showing the 

 change from circular to squarisli outline as the tip is neared. (Collection M. C. Z., nos. 8743, 

 8742, 3742.) X i 



Figs. 4, 5. Upper view of same bones shown in Figs. 2 and 3. The characteristic bracket-shaped depres- 

 sions and the foramina which open into them for the passage of blood vessels, are clearly seen. 

 Xf 



Figs. 6, 7, 8. The same three vertebrae shown in Figs. 1, 2, 3 respectively, but from the lower side. 

 In Figs. 6 and 7 appears the characteristic rounded pit into which open the two foramina seen in 

 Fig. 4 on the upper side. 



Fig. 9. Fragment from the upper part of a rib, in the collection of the Museum of Comparative Zoology 

 (no. 8744). X about f . 



Fig. 10. Centrum of a large vertebra showing the bases of the transverse processes and neural spine. 

 The epiphyses had not yet fused to the front and back ends of the centrum. (Collection of the 

 Society, no. 9698). X |. 



